Propeller.



ML B. MILLER.

PROPBLLER. APPLIOATION FILED MAY 7, 190B.

, Patented Mr. 9, 1909.

5 @mib/Lewes flttozncajo UNITED STATES PATEN'IA orrIcE.

MORGAN B. MILLER, or SAN JosE, CALIFORNIA, -AssI'GNoR or ONE-HALF 'ro GEORGE W.

HARVEY,A or SAN J'osE, eALIronNIA.-

rnornLLEn.

To all lwhom 'it may concern.:

Be it known that I, oRGAN B. MILLER,

a citizen of the United States, residing at Same.'

My .invention relates to propellers.

The object of the invention is the pro.

vision of a propeller blade which will cause the water displaced thereby to be projected in a solid stream in parallelism with the axis of the propeller.

Heretofore with many of the screw pro- I pellers in use twenty-tive per cent. of the power was lost by the water passing off of the propeller blades at the top Ainstead of at the rear edge. My inventionis ldesi ed to obviate these diiculties,-and broad y speaking consists in a blade whose curvature is suffi- 'cient to prevent the water from passing ofi the upper edge and insuring'its course of travel to be from the'leading to the trailing ed es of the blade.

ith these and other objects in view, the Inventlon conslsts 'of c ertam novel features of construetlon; comblnatlon and arrangement of parts, as will be more fully ldescribed and particularly pointed out in the appended clalms.

In the drawings, Figure l is an elevation of a ropeller, Fig. 2 is a section on the line 2-2 'o Fi 1, Fig. Sis a diagrammatic section on the hne 3`3 of Fig. 1, andFi 4- is a diagrammatie section of one of thelades taken on the line 4 4 of Fig.- 1.

Referring more especially to the drawings, represents the power shaft which enters a socket 2, formed In the propeller hub 3, and

is keyed therein in any suitable or approved.

manner. The outer end of the hub 1s provided With a plurality ofapertures 4, w ich are arranged at equal distances around the huband each provided with a serrated bottom 5. Asuitable bolt aperture 6 communicates with the aperturev 4, and is adapted'to 4'receive the attaching bolt 7, which threads into the socket pin 8, of the propeller blade 9. This pin is serrated on itsV bottom to mesh with the serrations 5 of the socket 4.

The blades 9 which are shown here are Specification of Letters' Patent, Application tiled May. 7, 1908. Serial No.'481,398.

' l :Patented auch e, 1909.

major and a minor axis through theirbody. The major axis a-b is'dished upon the are of aV circle whose radius is considerably greater than the arc of the circle upon which the body of the minor axis c-d is dished, and consequently we have a greater curvature in 4the blade inthe direction of its minor axis bolt 7 and raising the blades 9 slightl from their engagement with the serrated aces 5 of the sockets 4 any pitch desired may be given to them.

From the fore oing description, taken in' connection with t e accompanying drawings, thel construction and operation .of the invention will be readily understood Without requiring a more extended explanation.

Various changes in the form, proportion and the minor details of construction may be resorted to without departing from theprinciple or sacrificing any ofthe advantages of this invention as dened in the appended claims.

Having thus described my invention, what I claim and desire to secure'by Letters Patent is:

1. A ropeller blade having a dished engaging ace the curvature thereof being on arcs of circles and having a greater radius in a direction transverse from the propeller shaft than radially thereto.

2. In combination with 'a propeller shaft, of a hub secured thereto, and blades secured to said hub and having a dished engaging face the curvature thereof being on arcs of circles and having a greater radius in a direction transverse to the hub than radially thereto` l l 3. Apro eller comprising a hub, and a plurality of lades secured thereto each hav- In a major axis in a line transverse to the huil) and a' minor}haxis extendingradially preferably platter-shaped, that is having av '75 It will be noticed that by loosening the Ioo therefrom and a dished face, the curvature of which is greater along the minor aX-is than -along the major axis, and means for adjustl ably mountin the blades.- 5 4; A proe er comprising a hub having a lurality o sockets formed therein whose l ases are serrated, pro eller blades having studs formed thereon or engagement With/ the sockets, said studs having a serrated end 10 to engage the serrations in the base of the sockets, and means passin through the hub to engage the studs on the lades to hold the same 1n adjusted osition.

In testimony W ereof-I have hereunto vset my hand in presence of two subscribing 15 witnesses. MORGAN B. MILLER. Witnesses:

WEsLEY PIEPER,

FRANK' L. MAYHEW. 

